title: Light chain immunofluorescence in various nephropathies.
abstract: BACKGROUND
  Light chain immunofluoresence (IF) in renal biopsy is routinely used in the diagnosis of light chain deposition disease (LCDD), amyloidosis and cast nephropathy. Light chain predominance has also been reported in certain glomerulopathies like IgA nephropathy. However, pathogenesis of this pattern of deposition in various glomerulopathies is uncertain.
  
  
  OBJECTIVE
  To discuss the pathogenesis and utility of light chain IF in nephropathies.
  
  
  METHODS
  Retrospective study.
  
  
  METHODS
  The pattern of light chain IF and light microscopic diagnosis in 306 cases of various nephropathies was reviewed. Direct IF was done in all these cases with commercial fluorescence (Fluoresciene Isothiocynate ) conjugated polyclonal rabbit anti-human antisera against IgM, IgG, IgA, C3, C1q, kappa and lambda light chains.
  
  
  RESULTS
  Light chain deposits were seen in 240 (78.43%) cases. In IgA nephropathy, lupus nephritis and post-infectious glomerulonephritis (PIGN), lambda positivity was more as compared to kappa. Light chain deposits in LCDD and membranous nephropathy were more kappa type. The IF pattern in amyloidosis was not consistent.
  
  
  CONCLUSIONS
  The pathogenesis of light chain predominance in glomerulopathies is not clear and it depends on isoelectric point and size of the immune complex. Light chain IF should be performed routinely in all the renal biopsies.
authors.affiliation: Department of Pathology, Nizam's Institute of Medical Sciences, Hyderabad 500 082, Andhra Pradesh, India. megha_harke@yahoo.co.in
authors.forename: Megha S
authors.initials: MS
authors.lastname: Uppin
authors.forename: Aruna K
authors.initials: AK
authors.lastname: Prayaga
authors.forename: B H
authors.initials: BH
authors.lastname: Srinivas
authors.forename: Ram
authors.initials: R
authors.lastname: Rapur
authors.forename: Madhav
authors.initials: M
authors.lastname: Desai
authors.forename: K V
authors.initials: KV
authors.lastname: Dakshina Murthy
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D015922:Complement C1q / Q000032:analysis; D003176:Complement C3 / Q000032:analysis; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D007147:Immunoglobulin Light Chains / Q000032:analysis*; D007223:Infant; D007674:Kidney Diseases / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D003176:Complement C3; D007147:Immunoglobulin Light Chains; D015922:Complement C1q